A mobile communication system enables users to communicate on the move and has evolved to being capable of providing a high speed data communication service as well as a voice telephony service.
A Long Term Evolution Advanced (LTE-A) network is designed to provide a high speed packet-based communication of the data rate greater than, as much as 3 to 10 times, the data rate of a current service and aims at commercial deployment around 2014 timeframe.
Meanwhile, a lot of research on D2D communication has been conducted since the 2000s and aims to support data communications between nearby terminals located in the service area of the same or different base stations without assistance of radio access networks while reducing load of signals passing the radio access networks of base stations and the wired network connecting the radio access networks. In the following description, the term ‘LTE system’ is used to include both the LTE system of the related art and LTE-A systems.
The D2D communications underlying cellular communication system entail interference problem because the D2D communication between D2D terminals uses the same frequency resource as the cellular communication between a terminal and a base station. There is, therefore, a need for a method for controlling interference and managing the resource efficiently. In D2D communication, the D2D terminal has to be aware of the presence of nearby terminals and thus, a need exists for a method for advertising its presence and detecting the advertisement signals broadcast by other terminals. This advertisement signal has to be transmitted without disturbing the cellular communication between a base station and a terminal.
The D2D communication also has to support broadcast and multicast functionality for the terminal to transmit the same data to a plurality of other terminals as well as unicast functionality. Accordingly, a need exists for a method for allowing a terminal to receive signals broadcast by a plurality of terminals efficiently.
The above information is presented as background information only to assist with an understanding of the present disclosure. No determination has been made, and no assertion is made, as to whether any of the above might be applicable as prior art with regard to the present disclosure.